Brake slack adjuster for railway vehicles



Dec. 25,1923. ,478,957

, A. E. HAYWARD BRAKE SLACK ADJUSTER FOR RAILWAY VEHICLES Filed May 3. 1921 ww/dmi,

Patented Dec. 25, 1923.

UNITED STATES ARTHUR E. HAYWARD, OF SWINDON, ENGLAND.

BRAKE SLACK ADJUSTER FOR RAILWAY VEHICLES.

Application filed May 2, 1921.

Serial No. 466,124.

(GRANTED UNDER THE PROVISIONS OF THE ACT 01:" MARCH 3, 1921, 41 STAT. In, 1313.)

To all whom it may concern! Be it known that I, ARTHUR EDWARD HAYWARD, a subject of the King of Great Britain, residing in Swindon, England, a have invented certain new and useful Improvements in Brake Slack Ad'usters for Railway Vehicles for which have obtained patents in reat Britain, No. 105,-

629, dated April 25, 1916, and in India, No. no 4359 of 1919, dated April 14, 1919), of

which the followin is a specification.

This invention re ates to brake slack ad- 'usters for railway vehicles in which the rake rigging is so arranged that, when the w brake is released after being applied, the blocks are automatically withdrawn from rubbing contact with the wheels.

It has before been proposed to form on one or two members a plurality of indentations and for a pawl pivoted to a member to seat itself in one of the indentations to apply the brake while a second pivoted pawl was adapted to gather the slack as re uired.

am aware that it has also been proposed for the indentations to be on one member and for one pawl on another member to seat itself in one of the indentations to apply the brake and to skip an indentation when slack has to be gathered on the release of the brake.

The object of the invention is an improved method of slack gathering which en ables the second set of indentations and the second set of pawls to be dispensed with.

The invention comprises a particular method of slack gathering, wherein an element is pivoted to a member of the rigging and moves in a vertical plane, while the indentations are in a plane inclined to the radius line so that when the free end of a limb of the rigging seated in either of the indentations (except the last) fails, on the release of the brake, to synchronize with the same indentation (by the length of a tooth) the element drops and the limb is reseated in a fresh indentation.

The element can be so arranged that a straight slot therein would be at an angle to the horizontal, the indentations being formed on the upper side of the slot. 7

In a modified form the length of the radius line would be considerably reduced necessitating that the plane of the indentati s e on a cu ve hich would be eccentrio to its pivot to give the necessary dis tance apart to gather a more or less equal amount of slack each time the limb is reseated in a fresh indentation. The centre of the circle, of which the curved surface on which the indentations are formed is on a line drawn at right angles to a line at an angle to the radius line from the pivot of the element.

The depth of the indentations is such that when the slack has been gathered, the blocks, on release of the brake, can slack sufficiently to be clear of rubbing contact with the wheels. I

A spring, which may be of the coiled type, can be used,- one end of which would be connected to some part of the vehicle while the other end would be connected to the member to which the element is pivoted or to the element itself to exert a pull and keep it in the 011' position.

The accompanying drawings exemplify the invention, Figure 1 being a side elevation of the invention applied to a known type of brake rigging in which the power for the application of the brake is a hand lever. Figure 2 is a side elevation and Figure 3 a plan on an enlarged scale of the brake slack gathering member and the power rod.

Figure 4 is a side elevation of a modified form of the invention showing the power rod supported.

The usual brake mechanism is represented by the brake shaft a working in suit able bearings. 6 formed in hangers b, fixed to the frame 0 of the vehicle, or. and (1 arms formed with or attached to the brake shaft a, a is a lever arm also attached to or formed with the brake shaft a, d and d are pull rods, one end of each of which is connected respectively to the arms a and a of the brake shaft while the other .ends are connected to the brake block han ers or mechanism (not shown in the drawings), e is a power rod connected by means of an eye e to the forked end of an arm 7, secured to or formed in one with a tumbler shaft f while the other end is forked and connected to the brake gathering member m. The tumbler shaft 7 has its bearing in a hangin bracket g fixed to the frame 0 of the vehic e. The brake is applied by a hand lever j and is automatically returned to its normal position on the reverse movement of the said hand lever by a s rin connected to some part of the bra e riggin site side is connected to one end of the coiled spring 0, the other end 0 of the latter being connected to the eye of a rod p. The rod p is secured by adjustable means 72 to a bracket 1' secured to the framing c of the vehicle. The slack gathering member m has a slot through each of the plates,

and in alignment with each other, the slots being inclined and leaning towards the direction of the pull, one side of each of the slots havin a plurality of teeth m and the opposite si es ne plain. The pin a passing through the lever arm a when the brake blocks are new, seats itself in the to the base m thereof 0 bottom recess of one of the teeth m The length from the to m of the teeth the brake slack gatherin member should'be such as to permit the rake rigging, when the slack has been taken up, to slack back in order that the brake blocks may be released from rubbing contact with the wheels of the'vehicle.

.One end 0 of the coiled sprin o is attached to an eye m on the the slac gatherin member.

Tn a modified form of the invention as shewn in Figure 4 the pull rod 1' is shortened, one end vbeing connected to the brake slack gathering member t by means ofa pin t the member is as before described in the form of two plates one on each side of the eye on the end of the pull rod, while means such as a rivet t prevent the plates from getting out of alignment with each other. The slack gathering member I? has a slot through each of the plates, and in alignment with each other, the slots lying on a curve eccentric to its fulcrum as before described and leaning towards the direction of the pull, one side of the slots havin a plurality of teeth 25 and the opposite si es t plain. The pin a passing throu h the end of the lever arm when the bra e blocks are new, seats itself in the bottom recess of one of the teeth t. The end of the rod 1' in this arrangement has to be supported on a support 8, means such as a roller 8 being provided to relieve the fricathering tion of the rod when moved in the application or the release of the brake.

The coiled s ring 0 is attached to a proectlon 1' on t e rod 1' in order that when the pivoting pawl l is released the slack gathering member can be returned automatically to its normal or ofi position.

Having thus described the nature of the said invention and the best means I know of carrying the same into practical effect I claim 1. A brake adjusting apparatus for railway vehicles, comprising a power rod, a plate secured to said power rod having a slot inclined to the longitudinal axis of said ,power rod, said slot having teeth formed on one side thereof, a pivoted lever, a pin on said lever engaging with the teeth of said slot, a pull rod-pivotally connected to said pivoted lever and means for restoring said slotted late to normal.

' .2. A rake adjusting apparatus for railway vehicles, comprising a power rod, a

plate secured to said power rod having a slot inclined to the longitudinal axis of said power rod in the direction of the force exerted by said rod, said slot having teeth formed on one side thereof, the opposite side of the slot being plain, a pivoted lever, a

pin on said lever engaging with the teeth of said slot, a pull rod pivotally connected to said pivoted lever and means for restoring said slotted plate to normal. i

3. A brake adjusting apparatus for railway vehicles, comprising a power rod forked at one end, two plates, one on each side of said forked ends, each of said plates having an inclined slot, one side of each slot being toothed, a pivoted lever, a pin on said lever engaging. with the teeth of said slots, a pull rod pivotally connected to said pivoted lever and means for restoring said slotted plate to normal.

4. A brake adjusting apparatus for railway vehicles, comprising a power rod forked at one end,'two plates, one on each side of said forked ends, each of said plates having an inclined slot, one side of each slot being toothed, a pivoted lever, a pin on said lever engagin with the teeth of said slots, a pull rod, an spring means tending to move to saii slotted plates in opposition to the power ro In testimony whereof I have signed my name to this specification.

ARTHUR E. HAYWARD. 

